We are saying the same thing. Using an autoclave and epoxy/glass you could build a near bulletproof 18 ft 400 lb cat

As far carbon, the plants WERE prepared for Boeing and Airbus. The plants signed long term contracts to sell most of their production to the big companies. It's the rest of us that are in trouble

That makes sense Carl!

I dont think the rule. "carbon is expensive" is true these days..
A fully prepreg carbon nomex I 14 hull is 5% more expensive then a foam/carbon glass hull..

*shrugs*

The smaller builders here in Au are gearing up or already have geared up for prepreg carbon boats..
They use low temp uni prepreg which is comparable in cost or a little higher that some glass products.. (from memory $20 AuD a square meter 150 gm uni?) So two crossed layers +45/-45 for skins a little overkill but..) for the outer skin and a third layer of kevlar or glass for impact areas..

They use glass/vynl molds and simple wooden "ovens" with heater bars to "cook" to 100C.. Basically a box wich fits over the mold and the coils turned on for a set time.. With a thermo swicth to control the temp..

However the guys need to learn to vac a mold for good results..

Sorry to be beating "my own drum" here, but in the F16 class we allow carbon pretty much everywhere. Carbon rudderstocks and rudder/daggerboards are still less than halve the price than the glass/alu stuff from our competitors.

Stealth marine offer a full carbon set of hulls for only 1000 pounds more, on a total glass package price of only 6700 pounds. This standard package already includes a carbon mast.

It is my experience that certain carbon mast makers charge high prices for their products but that this is alo wholy unrelated to the price of the carbon cloth itself.

"Carbon = expensive" is simply not true

"certain builders/supplier = expensive" very much is true.

Wouter

Let's go over this again for those who don't read the whole thread.

Carbon is not expensive

To go from polyester/glass to epoxy/carbon is around $500 (hand lay-up)

However to get the best results, you need an autoclave. An autoclave will greatly improve the quality and repeatability of your composites. You can make it lighter for the same strength or stronger for the same weight compared to room temp and pressure cure

A 20 ft autoclave will cost $100,000 - $4,000,000. plus facilities. (The more expensive, the easier to use, the more boats at one time and the higher the pressure) If you are only building 100 boats a year, that is expensive.


If you own an autoclave you want to use it to build everything your company makes, to help pay for it. That is why most companies don't build polyester/glass and carbon/epoxy boats.

Using an autoclave you could build a 400 Lb 18 ft fiberglass catamaran that would last 15+ years


As for non-autoclaved epoxy composites, I would build my boat using them, I might buy a boat using them, I would NOT get on an airliner built using them. The quality of non-autoclaved composites is mixed, Sometimes it works great, sometimes it delaminates. It is rare for prepreg autoclaved composites to delaminate.